Sky Pencil Holly
What is the minimum temperature that Sky Pencil Holly will tolerate?
Certified GKH Gardening Expert
It appears that these can withstand down to -20 if they are established. As long as it is not a seedling, then it can withstand these temperatures.
Here is an article for more information on the care of these: https://www.gardeningknowhow.com/ornamental/shrubs/holly/care-of-sky-pencil-holly.htm